Grinding wheel



A1131}, wss. c', R G' 2,050,850

GRINDING WHEEL Filed March 30, 1934 W 7 wk;

Carl Kru nvvt/v To a,

Patented Aug. ll, 1936 GREG WEL Carl Krug, Frankfort-on-thc-Main, Germany Application March 30, 1934, Serial No. 718,134 In Germany October 15, 1931 7 Claims.

The object of the present invention is to enable a grinding tool with grinding discs clamped between flanges on the grinding shaft to be used for the very high grinding speeds which are now demanded because of the very advantageous increase in the grinding action. The high speeds are limited by the risk of fracture of the grinding disc which is occasioned by the centrifugal force. For reducing the danger of fracture and thus for solving the problem in question, according to the invention a ring of greater strength, for example a steel ring, is rigidly cemented in the central aperture in the grinding disc. This ring which is advantageously smooth and the wall thickness of which can be varied as desired, ex-

tends over the entire width of the grinding disc so that its end faces are flush with those of the grinding disc. Preferably the steel ring has recesses or an annular groove in the end surfaces for receiving loading blocks or other loading means for balancing any lack of uniformity in weight. In accordance with a further feature of the invention the height of the rim on the securing flanges on either side does not extend radially beyond the ring so that the clamping and securing forces are taken up only by the ring and not by the more brittle material of the grinding disc.

The new grinding tool is non-sensitive to jolting during transport and is not liable to errors in mounting. The complete balancing of the grinding disc, which is particularly important at high peripheral speeds, is attained with simple means and the entire grinding tool can be constructed very cheaply. The grinding disc can be used until 5 it is practically completely worn away and, in consequence of its cheapness, the steel ring can, be thrown away without detriment to economical working.

Some embodiments of grinding tools in accordance with the invention are shown by way of example in the accompanying drawing in which:

Fig. 1 shows a cross section through an embodiment which is suitable more particularly for grinding tools of narrow construction.

Fig. 2 shows a side view and Fig. 3 a section through a second embodiment which is more particularly intended for grinding tools of wider construction.

In the construction according to Fig. 1, which is intended more particularly for grinding tools of small size, the grinding disc 3 is carried on the periphery 2 of the supporting disc I which is expanded to form a ring. This grinding disc consists of the grinding body 3 and the steel ring 6 connected therewith by a layer of cement ll.

The steel ring has recesses turned in it for receiving the flange 5 of the supporting disc I and the flange 5a of the ring I on the rear side which in turn has a recess 8 for receiving the end of the supporting ring 2. The ring I and the sup-. 5 porting disc I are connected together near the periphery of the disc I by means of screws 6 so that by means of the ring 8 which abuts against the flanges 5, 5a the grinding disc 3 is. clamped in position. v l0 Theembodiment of the grinding tool as shown in Figs. 2 and 3, which is intended more particularly for larger tools, is difierentiated from that previously described solely in that the steel ring 4 which is connected with the grinding disc 3 by a layer of cement I l is let into a recess turned in the ring 2 of the supporting disc. The recess is closed by the flange 5 of the supporting ring I on one side and the flange 5a of the ring I on the other side. I

Whereas in the construction of the grinding tool according to Fig. l the rims on the securing flanges 5 and 5a are recessed with respect to the outer surface of the steel ring 4, in the construction according to Figs. 2 and 3 they project beyond the end surfaces of the steel ring.

In both embodiments the. steel ring 4 is provided with recesses or annular grooves 9 at the end surfaces in known manner for receiving loading bodies ill.

I claim:-

1. vIn a grinding tool the combination of a solid annulus of granular texture, a ring of greater strength in said annulus provided with a uniformly smooth circumferential surface, said annulus 35 and ring being secured together, by a layer of cement forming a rigid connection between said annulus and said ring, a circular support, and

radially extending clamping flanges associated with said support to embrace said ring.

40 2. In a grinding tool the combination of a solid annulus of granular texture, a metallic ring in said annulus provided with a uniformly smooth circumferential surface, said annulus and ring being secured together, by a layer of cement forming a rigid connection between said annulus and said ring, a circular support and radially extending clamping flanges associated with said support to embrace said metallic ring.

3. In a grinding tool the combination of a solid annulus of granular texture, a ring of greater strength in said annulus provided with a uniformly smooth circumferential surface, the side surfaces of said annulus and said ring being flush, said annulus and ring being secured together, by

a layer of cement forming a rigid connection between said annulus and said ring a circular support and radially extending clamping flanges associated with said support to embrace said ring.

4. In a grinding tool the combination of a solid annulus of granular texture, a metallic ring in said annulus provided with a uniformly smooth circumferential surface, the side surfaces of said annulus and said ring being flush, said annulus and ring being secured together, by a layer of cement forming a rigid connection between said annulus and said ring, a circular support and radially extending clamping flanges associated with said support to embrace said metallic ring.

5. In a grinding tool the combination of a solid annulus of granular texture, a ring of greater strength in said annulus provided with a uniformly smooth circumferential surface, said annulus and ring being secured together, by a layer of cement forming a rigid connection between said annulus and said ring a circular support and clamping flanges associated with said support to embrace said ring of greater strength, said clamping flanges extending outwardly in the radial direction of the tool to an amount not exceeding the extent of said ring.

6. In a grinding tool the combination of a solid annulus of granular texture, a ring of greater strength in said annulus provided with a uniformly smooth circumferential surface, the side sur faces of said annulus and said ring being flush, said annulus and ring being secured together. by a layer of cement forming a rigid connection between said annulus and said ring, a circular support and clamping flanges associated with said support to embrace said ring of greater strength, said clamping flanges extending outwardly in the radial direction of the tool to an amount not exceeding the extent of said ring.

'7. In a grinding tool the combination of a solid annulus of granular texture, a ring of greater strength in said annulus provided with a uniformly smooth circumferential surface and recesses in the end surfaces to receive loading 20 

